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What to look for on a pair of 350's

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captben

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Looking at buying a 86' Mainship 40 DC with a pair of Crusader 350's... So a couple of questions...

What can I expected for fuel burn? Transmissions are 2:1 throwing a 24x26 wheel.

It has been in storage for about 5 years. Anybody have any experience in resurrecting these engines from storage? What should I look for and expect once it gets in the water?

Thanks...
 
I suspect the fuel will be bad even if stabilized so that will need to come out. Also, is that a planing hull? I suspect so given the 454's but that is way too much prop for 2:1 reduction. I suspect it is 2.5:1 and still is probablt too much prop. That prop may work if you run at displacment speeds.
 
Whether or not the storage was performed properly will be a key question also. During the layup it has been exposed to numerous hot and cold cycles especially depending on where this vessel is located. You may want to take several steps to remove the plugs and determine if the clyinders are in good condition and the pistons free moving, fluids and filters will need to be removed and replaced, distributor inspected and depending on type, checked for freedom of movement in advance mechanism , points, wires and new batteries, shaft seals on stuffing boxes and rudders .....I really think it would be not that much different than a long term storage car. Pull the valve covers and peak inside. Seems like work but the alternative is a bit more effort

A SHORT story on my expectations once it the water.... I was expecting it to start. Instead, due to water ingestion and rust, she started, bent and broke several pushrods and had rusted frozen valves. So be diligent in insuring everything is loose where it is supposed to be
 
I have the same boat '86 40 DCMY. The trannies are 2.91 : 1 and I have original 24x27 3 blades. It will turn 4K but just barely with clean bottom. Sweet spot is 15 - 18 rpm, 7-8.5 kts about 8 gph. It will plan at around 15K ts - 2,800 rpm = 30 gph. I would pump out all the fuel you can which may be difficult as the tanks are fairly deep and the fill hoses bend going down. Our engine room is always bone dry, one advantage of putting the engines in the main cabin. Exhaust risers need replacing? Don' throw out the genny (kohler 7.5r) to quick. We tinkered with ours for hours but it has run great now for the past 3 years.
Tim
 
captben said:
It has been in storage for about 5 years. Anybody have any experience in resurrecting these engines from storage? What should I look for and expect once it gets in the water?

Thanks...
Click to expand...

5 years. If the engines weren't seriously prepared for storage, I'd NOT subject them to a starter just yet. That first revolution will be critical. Ditto on the stuck valve, bent rod thoughts. I'd definately take off the valve covers. I'd make sure that each valve is not frozen to its guide and look for obvious rust on the rocker arm wear surfaces, etc. IF the valves appear to be free, I'd still do that first revolution with a ratchet on the damper with the spark plugs out. If its stuck, I'd be inclined to use MMO or something like that inside each cylinder and let it soak. When you get the first couple of revs successful manually, I'd tackle the carb. Almost certain, it's not going to be happy. At MINIMUM, attempt to feed fresh fuel in and see if the accelerator pump works and the inlet valve holds pressure. Replace the raw water pump impeller and the oil. Drain it cold this time. Don't crank the engine until all these bits are worked out. The first attempt at starting should be successful; lots of cranking is not good and actually loads the cam/top end higher than a quick, successful start and run up to 1800rpm.
 
The transmissions are indeed 2.91:1. After I posted I thought it didn't sound right so I double checked the survey. The wheels are 4 bladed if that helps out at all...

If I end up picking up this boat I plan on installing a Floscan. I think having that on board will pay for itself during the delivery (200+ miles). Anybody have any bad experiences with Floscans or recommend something else? Might put a set of twinscan and twintach and just replace the tachs...

In regards to the engines... The mainship design makes for crawling around the engines really easy. I will take your advice and turn it a few times by hand before even installing the batterys...

Thanks gang! Can't wait to be listed on here as an owner!
 
Your saying the first trip is 200 miles? I would re-read diverdave's post as I know with my own boat which we used the season before for a few weeks. We had some serious problems when we launched in the following spring. Our first 5 trips we about 200 yards from the marina and to reduce the boredom we made a bunch of U-turns until we were confident enough to go further

I would love to see your experience be significantly great, but this boat has been sitting 5 years and you don't know how well it was prepared for storage. Looking forward to seenig you here as a new owner. Great people and great information
 
Join Boatus and get the towing insurance. If you are in the ocean it is like $125 and the great lakes is cheap. Something like $34 I think. About $25 to join I think.
 
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That's a lot of boat for small blocks to push. I suspect it will be a real gas hog on plane, so you might want to get used to off plane "trawler" running.

Frankly, I wouldn't consider a 200 mile trip in a strange boat without taking several 5 miles or less trips in it first. This is not a car that you can leave on the side of the road for a tow truck!

Jeff
 
fastjeff said:
That's a lot of boat for small blocks to push. I suspect it will be a real gas hog on plane, so you might want to get used to off plane "trawler" running.

Frankly, I wouldn't consider a 200 mile trip in a strange boat without taking several 5 miles or less trips in it first. This is not a car that you can leave on the side of the road for a tow truck!

Jeff
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No worries about that Jeff. I've seen many people drop their boats in the water after one winter, put the throttles to the dash and scratch their heads trying to figure out why they fried an engine.

The plan is for now to put at least 5-7 hours on the engines at the purchase marina to break everything in and leave with extra hoses!
 
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